Drilling procedure and apparatus



April 29, 1952 5. w. SEWELL 2,595,107

DRILLING PROCEDURE AND APPARATUS Filed March 19, 1948 2 SHEETSSHEET 1 S PEIME Mex/E2.

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Ben. C49. Seawall Savant/or E25 Clbborrzeg April 29, 1952 B. w. SEWELL DRILLING PROCEDURE AND APPARATUS 2 SHEETS-SHEET 2 Filed March 19, 1948 Fray-5 berz 5676301312 Urn/eater Clbborneg Patented Apr. 29, 1952 DRILLING PROCEDURE AND APPARATUS Ben W. Sewell, Tulsa, Okla., assignor to Standard Oil Development Company, a corporation of Delaware Application March 19, 1948, Serial No. 15,845

1 Claim. (01. 255-21) The present invention is directed to drilling apparatus. In particular the invention relates to a novel chain cutter adapted to cut boreholes in the earth.

The art of drilling boreholes into the earth has been very well developed. The conventional method now employed for drilling deep holes is the so-called rotary method in which there is employed a mud flush passing down through the center of a drill stem which supports and turns a cutting head. The mud is ejected from the drill stem adjacent to the cutting head. and then passes up the outside of the drill stem, performing various functions to facilitate the drilling. In the art of exploration for oil, there are a great many procedures which require the drilling of boreholes, such as the seismic method in which shot points up to two or three hundred feet may be drilled; the thermal method in which drill holes up to fifty feet are vnecessaryfor the location ofthermometers;

sampling methods in which it is desired to take the samples below the level of the uppermost water table, thereby necessitating drill holes of twenty feet or greater; the coring method in which drill holes ranging from two hundred to about a thousand feet are employed; and the like. It is quite commonly the case that these exploration procedures are performed in wild undeveloped country where there are dense forest growths and thick brush, or inextremely' arid regions. In either of these cases any drilling method which requires the use of water, drilling fluid, or mud necessitates the transportation of the necessary fluid to the location of each drill hole and as indicated, in certain areas this may be practically impossible.

In various types of mining also it is desirable to have a. drilling method by means of which relatively shallow holes vcan be drilled rapidly and cheaply.

The principal object of this invention is the provision of an apparatus for drilling earth boreholes, in which the drilling operation may, if desired, be carried out without the employment of drilling fluid.

An additional object of the present invention is the provision of a drilling apparatus which will drill a hole of a selected configuration and which greatly diminishes the danger of the hole deviating from the vertical.

Other objects and advantages of the present invention will appear in the following detailed description of the accompanying drawings in which:

Figure 1 is a front elevation of one form of apparatus according to the present invention and;

Figure 2 is a side elevation of the chain cutter of the present invention in operative position and;

Figure 3 is a cross section view along the line 33 of Figure 2 and;

Figure 4 is a transverse section along the line 4-4 of Figure 1 and;

Figure 5 is a vertical transverse section along the line 5-5 of Figure 4 and;

Figure 61s a partial vertical section along line 6-6 of Figure 2.

In essence, the apparatus of the present invention comprises an endless chain, the individual links of which constitute cutting surfaces, the chain being stretched over an elongated framework, carrying at either of its ends sprockbe added to the chain so that the entire assembly is adjustable in length. Combined with the framework is a driving mechanism for driving the sprockets and the chain while the assembly moves downwardly. I Referring to the drawings, numeral I designates a prime mover, the driven shaft of which enters and extends into a casing 2 in which it is coupled to a rotary table in the manner conventional in apparatus of this type. The rotary table has a shaft which extends upwardly in the form of a post 3, this post having for most of its length a non-circular cross section. Suspended from a suitable derrick by a cable 4 is the cutting chain assembly 5 which is disposed parallel to the post 3. The cable 4 has affixed to its lower end a U-shaped bracket 6, in which is journaled the shaft 1 of a sprocket wheel 8. The chain 5 rides on the sprocket wheel and is composed of individual links pivoted to each other, each link being a bucket-like member having a sharpened leading edge or lip in the direction of travel of the chain.

Ihe chain is held and stretched in position by an interior framework 9 made up of structural members Ill. The uppermost structural member terminates at its upper end in a U-shaped bracket I I, the free ends of which brace the shaft I. The lowermost structuralmember terminates at its lower end in a similar U-shaped bracket I3 between the free ends of which is journaled another at-ion proceeds.

sprocket wheel [4 over which the chain is engaged. The abutting ends of the structural members II) have flat faces and are bolted together so that similar members having both ends flattened may be interposed between the end structural members. In this way the framework can be made as long as desired simply by adding additional members. It will be understood of course that as each new section of framework is added there must be a corresponding addition of links to the chain.

Connected to the U-shaped bracket 6 by a suitable brace I is a gear box 16 which has clearance openings in its top and bottom walls so as to accommodate the post 3. The shaft 1 of the upper sprocket wheel extends into the gear box 16 and terminates therein in a bevel gear l1. Engaged with this gear is a horizontally disposed bevel gear [8, having as its center a bushing H! with a central opening corresponding in configuration to the periphery of the post 3. Beneath this gear is a horizontal plate 2%! bolted to the side wall of the gear box. Between the .plate 20 and the gear i8 is a coil spring 2; which serves to keep the horizontal gear !8 constantly in mesh with the bevel gear 1?.

At the start of the drilling operation, the entire assembly is in the position shown in Figure 1 with the gear box near the top of the rotating post 3. By suitably adjusting the tension in cable 4, an operator can impose as much as the full weight of the chain assembly as desired on the earth. A prime mover I is then set in operation and through the rotary table 2, rotates the post 3 which in turn drives the upper sprocket Wheel 8 and the chain 5. The bucket-like cutting links of this chain cut and remove earth as the oper- As the drilling progresses, the gear box It slides downwardly along the post 3 until such time as it becomes necessary to add additional structural members in the chain support and links to the chain. By the nature of this apparatus, cutting generally occurs in a substantially vertical direction. However, any tendencyfor the chain cutter to depart from the vertical can immediately be noted and compensated for by applying a horizontal force against the support 9 of the cutter. This may be accomplished, for example, simply by holding a bar against one of the structural members it]. Once the hole has been started there will be practically no tendency for cutting in a lateral direction since the weight of the chain, the supporting framework and the gear box will drive the mechanism downwardly. Application of the horizontal force will ordinarily not be necessary if the hole is started by digging a small pit which is frequent practice when drilling boreholes in the earth.

Having now fully described the present invention, What is claimed and desired to be protected by Letters Patent is:

An apparatus for cutting holes in the earth comprising an elongated vertical framework, said framework being constructed in separable sections and adapted to be lengthened by the insertion of additional similar sections, upper and lowersprockets having axles attached to the top and bottom ends respectively of said elongated framework, an endless chain stretched over said framework and engaged with each of said sprockets, and adapted to be lengthened, bucketlike links attached at evenly spaced intervals along said chain, said links having sharpened edges, a bracket supporting the axle of said upper sprocket and adapted to be suspended from a supporting cable, a gear box attached to said bracket, a bevel gear attached to the axle of said upper sprocket and vertically disposed within said gear box, a second bevel gear horizontally disposed within said gear box in meshed relation with said first bevel gear, said second bevel gear being provided with a central non-circular opening, a vertical shaft having a non-circular cross section corresponding substantially in shape to said non-circular opening, said shaft being slidably engaged with said second bevel gear, and means for rotating said shaft.

BEN W. SEWELL.

transactions crrnn The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date Re.10,027 Carley Feb. '7, 1882 556,349 Herza May 1'7, 1896 740,095 Daniels Sept. 29, 1903 758,781 Roelofson May 3, 1904 1,414,590 Seifert May 2, 1922 1,643,549 Donnelly et al. Sept. 27, 1927 

